stewart



(No Model.) 2. Sheets-Sheet 1. G. W. STEWART.

GAS ENGINE.

No. 381,488. Patented Apr. 17. 1888.

INVENTOH ETERS. Phnwtnhn n mr. wmin mn, D. c.

(No Model.) 2 Sheets-Sheet 2. G. W. STEWART.

GAS ENGINE.

No. 381,488. Patented Apr. 17, 1888.

WITNESSES: 1N VEN TOR,

Nv PETERS. Phmoutbognphm, wahin mn. D. c

NITED STATES "PATENT FFICEC GEORGE \V. S'IEiVART, OF NEWV YORK, N. Y.

GAS-ENGINE.

SPECIFICATION forming part of Letters Patent No. 381,488, dated April17,1888.

Application filed July 25, 1887.

Serial No. 245,160. (No model.)

To all whom it may concern.-

Be it known that I, GEORGE W. STEWART, of the city, county, and State ofNew York, have invented a new and useful Improvement in Gas-Engines, ofwhich the following is a specification.

This invention relates to gas-engines, its object being to automaticallyignite and explode the gas within the cylinder, so as to utilize thesame to its greatest efficiency, and thus obtain a very simple, cheap,and at the same time powerful engine. The manner in which I accomplishthis result is fully illustrated in the accompanying drawings, whichform part of this specification, and in which similar letters ofreference indicate corresponding parts.

Figure 1 represents a longitudinal vertical section showing the mannerin which the gas is supplied to the cylinder through the feedpipe 0 andthe supply-port d in the piston-rod a, also the igniting-ports e and 0.Fig. 2represents a horizontal section through the body of the engine andrelief or exhaust valve, to show the exhaust-port and illustrate theoperation of the valve, which will be hereinafter explained. Fig. 3represents an end view of the front end of the engine with a portion ofthe hoodf and funnel {1 broken away, showing the piston'rod a and aportion of the neckcasting in cross-section to better illustrate themethod of igniting the flame; and Fig. 4 illustrates an enlargedlongitudinal section of the valve i, to show the manner in which thesame is gripped to the stemj by means of the ashestus packing k.

The piston m, Figs. 1 and 2, is made of the usual form and provided witha cap, a, which is secured thereto, and which is provided with theordinary rod couplings, l, to which is secured the driving-rod 0. Thedriving-rod 0 is connected to the crank 12 of the balance-wheels s,which are provided with the usual shaftbearings, &c., to permit of itsperfect operation.

The piston-rod a is provided on its under side with a supply-port, as d,which is of a proper length to create a communicating channel'betweenthe feed-pipe c and the inside of the cylinder, as shown in Fig. 1.Through the neck of the casting, on its lower side, the feed-pipe c issecured, so as to connect its channel with that of the supply-port d. Onthe upper side of the piston-rod a, slightlyinside of its solid portion,ahole is provided, as e, which may be termed the igniting-port. Thisport is arranged to communicate at th proper moment of the stroke of thepiston with another igniting-port, c, which is provided in the upperside of the neck-casting and communicates with the funnel g. In the sideof the funnel g, as shown at a, Fig. 3, is a small port in the form of atip, by means of which the flame is communicated to the gas at theproper time, as will be hereinafter explained in connection with theoperation of the reliefvalve.

As show-n at 20, Fig. 2, the cylinder is provided with an exhaust-port,which communicates with the relief valve by means of the neck '0, whichsecures the cylinder 1* of the reliefvalve to the main cylinder of theengine. On each end of the cylinder rare secured the caps and t. Thesecaps are secured to the cylinder, as illustrated, the cap i beingprovided with a long threaded portion to permit of its being adjusted toregulate the stroke of the valve according to the stroke or speed of theengine, it being understood that when the engine is running at a highrate of speed it will require a longer stroke of the valve i in order tokeep the exhaust-passage open for a longer period of time. T oaccommodate this requirement the cap t can be unscrewed to any de sireddistance, thus lengthening out the cylinder 1' and increasing the strokeof the valve.

As illustrated-at b, Fig. 2, the cap t is provided with an opening,through which the stem j travels, which is sufficiently larger than thestem to permit of a free exhaust, also to admit the requisiteproportions of air into the cylinder on the return-stroke to createcombustion, while the corresponding opening in the cap 1. is therequisite size to permit of the free passage of the valve-stem andnothing more. The construction of the valve i is illustrated in Figs. 2and 4, which show the valve mounted upon the valve-stem,the valveconsisting simply of a tube solid at one end and a suitable plug toscrew in the opposite end, with a hole drilled through the solid end,and the plug and tube sufficiently large to accommodate an easy movementof the valve-stem, the

packing is being relied upon to hold the valve in position. One of thelugs l, as shown in Fig. 2, is extended and bent at rectangle, so as toform an arm, to which the end of the valve'stem is secured, as shown inFig. 2, so that the valve-stem has the same travel of stroke as thepiston. The distance between the Valve i and the cap or valve-seat itbeing much less than the stroke of. the piston, it requires that thevalve 6 be secured to the stem with sufficient grip to be carried backand forth and held against ltsseat at each end of the cylinder, but withsufficient freedom to permit the stem to slide through the valve andcomplete its stroke, as described in the oper ation of the enginehereinafter.

The method of igniting the gas is illustrated I in Figs. 2 and 3, whichshow the burner g tapped into the main supply-pipe c, from which itreceives the requisite flow of gas to keep a proper-sized blaze burningconstantly in front of the igniting-port u, as shown in Fig. 3.

The manner of mounting the engine is to provide it with legs, as shownat A, Figs. 1 and 3, and screwing the said legs to the bed-plate orfoundation. This manner of mounting engines of this character is socommon that it is thought hardly necessary to go into any furtherdescription, excepting to say that as a novel and new feature I make thebed-plate in the form of a box and utilize its interior space for thepurpose of storing the gas when so desired. In other words, it is agas-reservoir.

The operation of my engine is as follows, assuming that the gas isburning from the burner y, as shown in Fig. 3: Gas, being admittedthrough the supply-pipe 0, will flow through the supplyport or channel6! of the piston-rod into the cylinder. The piston is then-movedforward, and the supply of gas is cut off by the solid portion of thepiston-rod covering the supply-pipe 0. After the piston has cut off thesupply of gas, the igniting-ports e and e are in communication with eachother, so that a sufficient jet of gas will escape through the saidigniting-ports into the funnel g, as shown in Fig. 3, and will beignited by the blaze from the burner y through the tip a. The gas in thecylinder will then explode and expand its forces against the piston,thus driving it to the limit of its stroke. This operation is repeatedautomatically with each stroke of the piston, depending upon the forceof the balance-wheels to complete the return-stroke, unless it should bein cases where a twin engine is built.

The operation of the exhaust-valve is as follows: The side of the pistonbeing slightly cut away to permit of a free exhaust, as shown at 20,Fig. 2, air is admitted into the cylinder through the cap t insufficient quantities to mix with the gas being supplied and create thenecessary combustion when ignited. At the beginning of the stroke, asabove de-' scribed, the Valve 73 begins a corresponding travel to thatof the piston, being carried by,

the valve-stem j and arm which is secured to one of the legs Z.' Thevalve 1 travels with the valve-stem until the valve has been seated tothe inside of the cap or seat t, and the supply of air is then cut off.The valve remains and keeps the exhaust-ports closed while thevalve-stem completes its stroke with the piston. Immediately upon thebeginning of the return-stroke, the valve 2', being clutched to the stemby its asbestus packing, will travel with the stem, and thus open theexhaustport, leaving the exhaust a free exit, as indicated by thearrows. peated at each stroke, the side of the cylinder being slightlyslotted to accommodate the arm which carries the valve-stem.

Having thus described my invention, what I claim, and desire to secureby Letters Patent,

is as follows, to wit:

1. An exhaust and air-supply mechanism which consists of the cylinder r,provided at each end with the caps or seats t and t, the valve-stem j,carried by the engine-piston and provided with a valve, as 2', arrangedto be seated by the valve-stem before the same has completed its strokeand to be unseated again at the beginning of its return-stroke, as setforth and specified.

2. A gas-engine constructed of a proper cylinder and piston, as m,secured to apiston-rod extension,as (1, provided with the supply port orchannel d and igniting-port 6, arranged to communicate through theigniting-port c with the funnel g, in combination with a gas-supplypipe, c, and burner 1, as and for the purpose specified. v

3. A gas-engine constructed of a suitable cylinder with the piston m,piston-rod extension a, provided with the supply-channel (2, arranged tocommunicate with and receive gas from the supply-pipe c, the same to beignited, as described, through the ports 6 and e, in combination with.an exhaust and air-supply mechanism, consisting of the cylinder r andprovided with the caps t and t, theValve-stem 3', carried bythe pistonm, and provided with a valve, as i, all arranged to operate asdescribed, and for the purpose specified.

4. A gas-engine constructed of a suitable cylinder and piston, as m, androd a, provided with the supply and igniting ports, as described,thesupply pipe c,and igniting-burner all arranged to operate as described,in combination with a relief mechanism, which consists of the valve t,arranged to be operated by the valve-stem j within the cylinder 1' insuch a manner asto close, the exhaust-port before the stroke of thepiston is completed,and to open the same again at the beginning of thereturn-stroke, as described.

In testimony that I claim the foregoing improvement in gasengines, asabove described, I have hereunto set my hand this 12th day of July,1887. w

' GEORGE W. STEWART. Witnesses:

STEPHEN J. Cox, SAMUEL KILPATRIOK.

This operation is re- IIO

